U.S. Pat. No. 6,747,420 B2 discloses in its title a drive circuit for light emitting diodes and discloses in its Figures a driver (circuit 4), a load (LED 1), a digital controller (μC 3) and a converter (R-shunt 6) for converting an analog current signal defining a current flowing through the load into an analog voltage signal. This analog voltage signal is supplied to the driver. The digital controller controls the driver and controls the converter, and the converter instructs the driver. This is a relatively complex and relatively inefficient construction.